Noun

The use of a single characteristic or name of an object to identify an entire object or related object.

(countable) A metonym.

{{examples-right, caption=metonymy , examples=*The White House released its official report today. — "The White House" for "The presidential administration"
* The Crown has enacted a new social security policy. — "The Crown" for "The government of the United Kingdom".
* A crowd of fifty heads — where "head" stands for person.
* Put it on the plastic — material (plastic) for object (credit card), width=60%}}

Noun

(uncountable) The property of a word of sounding like what it represents.

* {{quote-book

, year= 1553 , year_published= 1909 , author= , (Desiderius Erasmus) , by= , title= Arte of Rhetorique , url= http://books.google.com/books?id=6p0xbOGIz2MC&pg=PA173 , original= , chapter= , section= , isbn= , edition= , publisher= Clarendon Press , location= Oxford , editor= , volume= , page= , passage= A woorde making called of the Grecians Onomatapoia , is when wee make wordes of our owne minde, such as bee derived from the nature of things. }}

(countable) A word that sounds like what it represents, such as "gurgle" or "hiss".

(uncountable, rhetoric) The use of language whose sound imitates that which it names.